Remote control system



Aug. 24, 1943.

C. J. HULL ET AL.

REMOTE CONTROL SYSTEM Filed Sept. 5 1940 2 Sheets-Sheet 1 FA fl. 0550A s.

Aug. 24, 1943.

C. J. HULL ET AL REMOTE CONTROL S YSTEM v Filed sept. 3, 1940 INSULATION 79 5l E 58\ J( 74 75 v 4 57 *f7 40 50 6l a N-uf I FIG. 2

INVENTORS.

CHARLES J. HUL L BY FR D OSBORNE. j

' TTORNEYS.

Patented Aug. 24, 1943 4 REMOTE CONTROL SYSTEM Charles J. Hull, North Tonawanda, and Fred H. Osborne, Snyder, N. Y., assignors to The Rudolph Wurlitzer Company, Cincinnati, Ohio,

a corporation s Application September 3, 1940, Serial No. 355,204

. invention relates to a remote control appratus which is particularly adapted to the selective control of automatic record changing phono- .graph but may be used for other purposes as well.

One object of the invention is to simplify the apparatus necessary for remote control of a machine having a number of different operations to be selectively actuated.

.Another object of .the invention is to reduce the number of electrical conductors required between the remote control point and the controlled machine. Heretofore a relatively large cable containing at least one conductor for each operation has generally been used yfor this purpose except when extremely complicated signal transmitting and receiving apparatus has been employed. In the present invention, in its preferred form, a single electric circuit which may consist of two metallic conductors or a single conductor and a ground connection is employed. The circuit may be operated on relatively low voltage so that the cable may be relatively small in diameter since theinsulation may. be designedfor mechanical strength rather than for electrical resistance.

v mitting apparatus located at a remote control station. Fig. 2 is a diagram of the receiving apparatus located at a local station adjacent the machine to be controlled, mechanical parts being shown in perspective and electrical connections l diagrammatically shown. For the sake oi?v clearness the stationary structure of the receiver is omitted. Y

Referring now to Fig. 1, power for operating the transmitter is supplied to a pair of conductors Ill and I I from any suitable source. Preferably said conductors are connected to a plug I2 which may be inserted in the usual wall receptacle or a lighting system from which alternating current at 110 volts, 60 cycle isobtained. The transmission apparatus includes a motor I3 adapted to turn a starwheel I4.. a limit switch and a multi-point switch I8 `through suitable shafts and gearing not 3 Claims. /(Cl. 177-380) shown.' The elements I4, I5 and I6 are so. connected that each makes one revolution during the same period of time. There are also included a mainrelay Il, a safety relay I8, a manually operable selector switch I9 and a resistor 20.

The manual selector switch I9 may be operated to establish electrical connection selectively between a conductor 42 and any one of a, series oi'v switch points 2l, herein shown as eight in number. .As many such points may be provided as there are operations to be selectively performed by the controlled machine. The switch I6, when turned by the motor I3, successively establishes electrical contact between a. conductor 22 and each of a series of switch points 23, each of which corresponds with one of the 'points 2l vand is elec-- trically connected thereto by one of a series of conductors 24 providing a plurality of parallel current paths. The starwheel I4, when turned by the motor I3, periodically closes an impulse switch 25 and each such closure takes place in timed relation with the movement of switch I6 from one of the points 23 to the next.. The relay I1, when energized, closes a set of normally open switches 26, 2l and 28. The relay I8, when energized, closes a normally open switch 29. A transformer 30 having its primary winding connected to the power lines I and II supplies alternating current to a pair of conductors 3| and 32' at a suitable 1ow voltage for the control circuit to the receiver. An initiating switch 33 is preferably coin controlled and is momentarily closed upon receipt of a. coin by any well known mechanism now used for the purpose. provided with a pair of brushes '34 and 35 between which an electrical contact is established inall positions of the switch except thev initial position shown in the drawings.

1n the normal idle position of the transmitter I theV parts are as snown in Fig. 1 in which the switch I6 is in an initial position with its contact nngers between two of the points 23 and the limit switch I is in open. circuit position. The switch and the switches controlled by relays I1 and I8 are open. Assuming that the invention 1s in use for the control of an automatic record changing phonograph, each of the contact points .2l will be numbered to correspond with the number of a record to be played as shown by a suitable inaex. ln the operation of the transmitter the operator irst places the manual selector switch I9 in position to make contact with the point 2| corresponding to a desired record. He then inserts a coin, momentarily closing the initiating switch 33. The operation of said switch The limit switch I5 is completes a circuit for the relay I1 from power line through switch 33, a conductor 35, relay I1 and resistor 20 to power line II. The switch line II. The iirst movement oi the motor turns the limit switch I5 to close the connection between brushes 34 and 35 and to complete a retaining clrcuit for said motor from the power line through said switch-and a conductor 31. The motor thus continues to. operate even after relay I1 is deenergized until a complete revolution o! the starwheel I4, switch I8 and switch I5 has been made.

The operation of switch 28 when relay I1 is energized conditions a connection from the secondary winding of transformer 30 through the conductor 3|, switch 28, a conductor 39 and switch 25 to a conductor 4U. This connection is intermittently completed by operation oi.' the switch 25. The conductor 32 leading from the second terminal oi the transformer is connected through the winding of relay I8 to a conductor 4|. The conductorsv 40 and 4I lead to the receiver shown in Fig. 2 and constitute the external conductors o'f the control circuit between the transmitter and receiver. At the receiver said conductors are connected to a relay 50.

With the motor I3 in operation and the relay :v

|1Aenergized, the opening and closing of switch 25 by the rotation of the starwheel I4 impresses on the external control circuit a series of electrical impulses or signals spaced at regular intervals and adapted to energize the relay 50. At the same time, the switch I5 is turned by the motor I3 so that each of said signals occurs just prior to the completion of contact through one oi.' the points of said switch. When switch I5 reaches the point 23 corresponding to the selected point 2|, a connection is made between opposite terminals of the relay I1 through the conductor 42, switch I9, one of the conductors 2,4, switch I5 and the conductor 22. This connection short circuits the coil of relay I1 and deenergizes the same. The provision of the resistor prevents the short circuit from imposing an overload on the power lines I0 and When relay |1 is deenergized, switch 28 is opened and no further impulses can be impressed on the external circuit, even though switch continues to operate. Thereafter the motor continues to run until limit switch I5 and switch I6 have returned to their initial positions, whereupon contact is broken at switch I5 and the motor is stopped.

It will be apparent that during the time that relay I1 is energized a series of electrical im-l pulses is transmitted and the number of such impulses in the series depends upon the selective setting of the switch I9. It will also be seen that current passes through the winding of relay I8 at each such impulse. The characteristics of said winding are so chosen that the relay does not respond to the normal current flow but only to an overload which may be imposed if there is a short circuit between the conductors 40 and 4I at any point between the transmitter and the receiver. In case of such an overload, the relay I8 closes switch 29. Said switch is connected in parallel with the winding of relay I1 and short circuits 'the same to stop further transmission oi signals. Relay I5 thus serves as overload protection for the external circuit and as protection against'tampering with said circuit.

Referring now to Fig. 2 in which there is disgrammatically illustrated the receiving apparatus located at a station adjacent the controlled machine, there are shown therein the two conductors 40 andI 4I leading from the transmitter in the remote control station and connected tothe relay 50. Said relay is adapted to close a switch 5| in response -to each impulse or signal received from the transmitter. There is also shown an electromagnet 52, an electromagnet 53, a series of magnets |15 and a magnet |55. Power for operating said magnets is supplied from a pair oi power lines 54 and 55 connected to a plug 56 which may be inserted in `a suitable receptacle, preferably carrying the common 110 volt, 60 cycle alternating current. The series of magnets |15 corresponds to a series o! magnets oi the same number shown in Wilcox Patent No. 2,002,236 when the invention is to be used to control a machine of the type shown in said Wilcox patent, In that patent each of the magnets |15 controls the selection for playing of an individual phonograph record. In other types of machines, said magnets may control different operations of the machine which are to be selectively actuated. The magnet |58 may correspond to the magnet of the same number shown in said Wilcox patent which serves to start the operation of the Wilcox machine to play the selected record.

The magnet 52 is connected across the power lines 54 and 55 by switch 5| at each actuation of the relay 50. Said magnet is arranged to attract an armature 51 which is piyotally mounted at 58 on a fixed support. Said armature is adapted to engage the teeth of a ratchet wheel 59 mounted on a shaft and normally urged in the clockwise direction by a torsion spring 5I. The shaft 50 carries an electrical contact nger 52 adapted to engage a series of contact points 53 each of which is connected to one of the magnets |15'by one oi a series 0I conductors 54. A stop pin carried by the ratchetwheel 59 is adapted to engage a stationary stop member 55 and is normally held against said stop member by the spring 5| when the parts are in their normal idle position. In this position the nger 62 1s out of engagement with the switch points 53. Successive actuations of the armature 51 move the ratchet wheel 59 to bring said finger successively into engagement with said switch points. A pawl 61 pivotally mounted at 58 on a iixed support is normally held in the position shown in the drawings out of engagement with the ratch wheel by a rod 59 having its lower end horizontally bent to engage the under surface of an armature 10. lSaid armature is pivotally mounted at 1| upon a xed support and is drawn upwardly against the action of a tension spring 12 by the magnet 53 when energized. A tension spring 13 normally urges the pawl 51 toward engagement with the ratchet 59. The relative characteristics oi the springs 12 and 13 are such that the spring 12 holds the pawl free o! the ratchet unless magnet 53 is energized. When said magnet is energized the spring 13 is free to draw the pawl 51 into engagement with the ratchet 59 to prevent clockwise rotation thereof.

The armature 51 is provided with an upwardly extending hook 14 engaging a lever arm 15 which is urged upwardly by a tension spring 15. Said lever arm is plvotally mounted within the housing of a time delay mechanism 11., Said mechanism is of a well known form adapted to permit unrestricted downward movement of the lever 15 leaves of a normally closed switch 19 and a normally open switch 80 and retains Asaid switches in-their normal position. vDownward movement of the lever arm 15 permits the position of said switches to be reversed.

In the operation of the receiving apparatus a. series of electrical impulses from the transmitter actuates the magnet 50 and repeatedly 'closes the switch 5|. Each closure of switch 5| actuates magnet 52 which thus serves as a high voltage repeater for magnet 50. Each actuation of magnet 52-moves the ratchet wheel 5| one step in the counterclockwise direction and engages the nger 62 with one of the points 63. The first actuation of magnet 52 draws the lever arm 15 downwardly, opens switch 19 and closes switch 80. The closing of switch 80 completes a circuit from the power line 55 through a conductor 8| to the magnet 53, thus energizing said magnet and permitting the pawl 61 to engage the ratchet 59 to prevent reverse rotation thereof. The characteristics of the time delay device 11 are such that the lever 15 can not be raised far enough to open switch 80 for a predetermined time interval afterA said lever has been drawn to its lower position. This time interval is longer than the normal interval between impulses and since each impulse results in movement of the lever 15 to its lower position, the switch 80 remains closed as long a s a series of impulses is in progress. The magnet A 53 thus remains energized throughout a series of impulses and the pawl 61 remains in engagement with the ratchet wheel 59 and permits said wheel to be moved one step for each impulse in the series. When the last impulse of a series is received the finger 62 rests upon a point 63 determined by the number of impulses in the series and corresponding to the selected magnet |15.

The magnet 53 closes a normally open switch 82 connected by a conductor 83 to the magnet |58 and through the shaft 6|) to the finger 62. The closure of said switch at the first impulse of -a series has no immediate result. When a series of impulses ceases, the spring 16 slowly draws the lever 15 upwardly against the action of the time delay mechanism 11. In the upward movement of said lever, the switch 19 is closed before switch 80 is opened. The closure of switch 19 completes a circuit from the power line 55 through a conductor 84, the selected magnet |15, the corresponding switch point 63, finger 62, shaft 60, conductor 83 and switch 82 to the power line 54. At the same time a parallel circuit is completed through the magnet |58. 'I'he completion of these circuits operates the selected magnet |15 and the magnet |58 to initiate the operation of the phonograph to play the record corresponding to said selected magnet. Said upward movement of the lever 15 opens switch 80, deenergizes magnet 53 to break the last mentioned circuits and to withdraw the pawl 61 from the ratchet wheel 55. The spring 6| thereupon returns the ratchet Wheel 59 to its initial position and the parts are in readiness for another cycle of operation.

From the foregoing specification it will be apparent that a single electric circuit is used between the transmitter and receiver. 'I'he transmitter is adapted to impress on said `circuit a series of regularlyspaced electrical impulses Brsignals. The number of such signals in a given series is determined by the manual setting of the. selector switch I9. 'Ihe receiver operates in response to said impulses to select the control circuit for one of the magnets |15, the selection depending upon the number of impulses in a series. In response to the cessation of said impulses, the selected circuit is momentarily closed and then reopened and the parts are permitted to return to initial idle position.

The invention has been described in one of its preferred forms, the details of which may be varied without departing from the scope thereof as defined by the appended claims. The invention claimed is:

1. Inv a remote control system havingan electric control circuit extending from a remote control station to a local station adjacent a controlled machine, the subcombination of a motor operated impulse switch in said circuit at said remote station, a motor for operating said switch, a second switch in said circuit, initiating means for operating said second switch to render said impulse switch effective in making and breaking said circuit and for simultaneously starting said motor, apparatus automatically operable after a predetermined period of motor operation to reverse said second switch to render said impulse switch ineffective, said apparatus being selectively operable to vary said period below a predetermined maximum, and a limit switch connected to control said motor and to stop the same at the end of a predetermined period of operation at least as long as said maximum period.

2. In a remote control system having an electric control circuit extending from a remote control station to a local station adjacent a controlled machine, the subcombination of an impulse switch in said control circuit at said remote station, a second switch in said circuit adapted to render said impulse switch effective or ineffective in making and breaking said circuit, a relay operating said second switch, a manually operable multi-point selector switch, a second multi-point switch having points corresponding to those of said rst multi-point switch, electrical connections between corresponding points of said multipoint switches forming parallel current paths, a motor operating said impulse switch and the second of said multi-point switches, manually operated means for operating said relay to make said impulse switch effective and for simultaneously starting said motor, electrical connections including said multi-point switches for reversing said relay to make said impulse switch ineiective when a. circuit is completed through one of said parallel current paths, and means including a limit switch operable thereafter to stop said motor when said motor driven multi-point switch has been returned to an initial position.

3. In a remote control system having an electric control circuit extending from a remote control station to a local station adjacent a controlled machine, the subcombination of a make and break device in said control circuit at said remote station, a switch in said circuit connected in series therewith, a relay operating said switch and adapted to close the same when energized and to open the same when deenergized, a manually operable multi-point selector switch, a second multi-point switch having points corresponding to those of said first multi-point switch, electrical connections between corresponding points 4 asamso of said multi-point switches forming parallel current paths, a motor operating said make and break device and the second oi' said multi-point switches, manually operated means for setting said relay in energized condition, circuits controlled by said relay when energized to start said motor, s aid relay being ineiIective to stop said motor when deenergized, electric connections inciuding said multi-point switches for deenergizing `said relay when connections are completed through any one of said parallel paths, and means including a limit, switch operable thereafter to stop said motor when said motor driven multi-point switch has been returned to an initial position.

CHARIES J. HULL.

FRED H. OSBORNE. 

